The invention relates generally to surgical suturing devices, and more particularly to intra-abdominal suturing devices designed for closing puncture wounds created by surgical trocars and similar puncturing devices.
Minimally invasive surgery is a revolutionary new technique that has replaced many standard invasive surgical operations requiring large incisions with operations utilizing very small incisions. In this technique, access to the surgical field is made through very small incisions (generally 5-18 mm in diameter) via a surgical trocar. These trocars typically have a diameter of, for example, between 3 mm and 30 mm and a length of about 150 mm (6 inches). Tubes are then inserted through the incision to permit the further introduction of miniaturized instruments and laparoscopes that can be manipulated by a surgeon while viewing the surgical field on a television monitor. This technology affords the patient considerably less pain and disfigurement, and a much faster recovery. The rapid return of the patient to productive activity further reduces the ultimate cost of the surgery.
Although trocars are widely used to puncture the abdominal wall as a first step in minimally invasive surgical techniques, such use creates several clinical problems. The very small size of the incision and the somewhat awkward access to the interior facies of the tissues surrounding the incision make closure of the incision problematic and time consuming. For example, one method requires the introduction of a pre-threaded suture needle approximately 3-5 mm from the edge of the original trocar incision. The surgeon views the needle via a laparoscope as it pierces the abdominal wall. The surgeon then grasps the ligature in the pre-threaded needle with a forceps, eventually secures it, passes it to a needle that has been introduced on the opposite side of the surgical defect, and withdraws the needle up through the other side of the incision, through the abdominal wall, and ties off the suture. The knot is generally tied under the skin to avoid residual external scarring.
Because the surgeon cannot directly visualize the exact position of the needle until after it has passed completely through the abdominal wall, several insertions may be required in order to place the needle at an ideal and proper distance from the trocar incision. The distance from the needle location to the original incision is critical in that the needle must be far enough from the trocar incision to secure an optimal amount of abdominal wall tissue. If the needle distance from the incision is too small, an insufficient amount of tissue will be secured with a consequent risk of inadequate closure of the surgical defect. This may result in subsequent herniation of the omentum or bowel. However, if needle distance from the point of the original trocar incision is too great, incision closure will result in excessive tissue being grasped, and the patient will be left with an unsightly “knot” of tissue. Aside from attendant awkwardness and the problems resulting therefrom, this method is time-consuming and often produces only marginal closure integrity.
Another difficulty associated with this mode for closure is associated with obese patients who present considerable fat in the abdominal region. Because the abdominal wall of an obese patient may be several inches thick, it is extremely difficult, tedious and time consuming to approximate the fascial tissues with a suture. Often times, following removal of a large trocar, the puncture site needs to be enlarged to accomplish this, thus negating some of the advantages of endoscopic surgery previously discussed.
Another common technique for closing a trocar incision comprises the re-approximation of the fascia and subcutaneous fat by means of a small needle introduced through the trocar skin incision from outside the body at the termination of the procedure. The difficulty with this technique is that the edges of the fascia are not easily visualized, with the result that tying the ligature may or may not effectively re-approximate the edges of the fascia. Certainly the peritoneal defect is not effectively closed by this approach because the suture is not placed deeply enough.
Often times, closure of the trocar incision is nothing more than skin deep, the deeper layers of the fascia remaining free. Failure to make complete closure of the incision entails a significant risk of delayed bleeding (occurring after the abdomen is deflated and the tamponading effect of the inflated abdomen ceases), or the possibility of herniation of either omentum or bowel into the subcutaneous opening.
Occasionally, the peritoneal defect may be approximated by a traditional, curved-needle suture ligature that is placed from within the abdominal cavity under direct vision. The knot is then tied either by means of an intra-corporeal or extra-corporeal knot-tying technique. This approach is rarely used because it is cumbersome, requires a high level of skill, and is still not optimal as it ensures only that the peritoneum is closed, closure of the more exterior fascia being purely speculative.
In view of the foregoing there is a clear need for a closure tool or suturing device, and a method of incision closure, that is accurate and reliable, and that does not require an excessive amount of time to complete. There also exists a need for a surgical device and method that can be utilized by surgeons having various skill levels.